A specification document in system/software development has been confirmed for a state free from contradictions by means of a manual review. However, there is such a problem in that inspection of a document in a large quantity including redundant descriptions requires cost (time and labor), and oversights may occur during the manual inspection.
In Patent Literature 1, there is disclosed a method of detecting a contradiction in a specification document. In Patent Literature 1, conditions (preconditions, postconditions, and invariants) relating to validity of information on a specification document are set based on a use case, an arbitrary operation is extracted from an event flow, conditions (preconditions and postconditions) relating to the extracted operation are set, and whether or not the set conditions are satisfied is determined by using the conditions relating to the operation. However, in Patent Literature 1, it is assumed that the specification document is strictly set as conditions for the use case, and there is such a problem in that labor for preparation before analysis is required in advance for each specification document.
In Non Patent Literature 1, there is disclosed a method of identifying a conflict between requirements. According to Non Patent Literature 1, a requirement is manually classified into attributes, and it is estimated that the relationship of the conflict exists between requirements in a dependent relationship between predetermined attributes. However, in Non Patent Literature 1, the dependent relationship between requirements or a relationship between a requirement and an executable code is necessary, and these relationships need to be prepared in advance. Therefore, there is such a problem in that labor for preparation before analysis is required in advance for each specification document.